Integrated circuits may have external electrical connections which include solder balls, sometimes referred to as solder bumps or solder pillars. Under bump metal structures may be formed between the solder balls and underlying top level metal interconnects in the integrated circuits. The under bump metal structures may desirably block or slow consumption of metal in the top level interconnects by formation of intermetallic compounds with the solder. Forming the under bump metal structures may involve one or more photolithographic operations, which may undesirably increase fabrication costs and complexities of the integrated circuits.